law enforcement agencies across the bay area are out in force, trying to keep drunk drivers off the road. in the south bay, the crackdown includes special roving patrols. nbc bay area's monte francis spent part of the evening with the chp on one of the patrols. he is live in san jose with the story. monte? >> reporter: terry, good evening. the reality is for many people today is a day devoted to drinking, and the highway patrol officers we spent some time with tonight say this is an active weekend for dui in the south bay. chp officers brandyn thompson and pierce visare on the look o >> anything out of the order, erratic braking, swerving in a lane, making erratic lane changes. anything that doesn't look normal. >> reporter: an expired registration gives them the chance to check for signs of dui. >> may i have your license, your registration and insurance please? >> yeah. shirks doing about 77. so max speed on this way was 65 miles per hour. >> reporter: a speeding car leads to another stop and another sobriety test. >> look at my finger. great. >> reporter: minutes later that. >> respon